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bad-dunder-method-name (PLW3201)

Preview (since v0.0.285) · Related issues · View source

Derived from the Pylint linter.

This rule is unstable and in preview. The --preview flag is required for use.

What it does

Checks for dunder methods that have no special meaning in Python 3.

Why is this bad?

Misspelled or no longer supported dunder name methods may cause your code to not function as expected.

Since dunder methods are associated with customizing the behavior of a class in Python, introducing a dunder method such as __foo__ that diverges from standard Python dunder methods could potentially confuse someone reading the code.

This rule will detect all methods starting and ending with at least one underscore (e.g., _str_), but ignores known dunder methods (like __init__), as well as methods that are marked with @override.

Additional dunder methods names can be allowed via the lint.pylint.allow-dunder-method-names setting.

Example

class Foo:
    def __init_(self): ...

Use instead:

class Foo:
    def __init__(self): ...

Options